ezmsg.dashboard.backend.services.stream_tap.DEFAULT_WINDOW_SECONDS

DEFAULT_WINDOW_SECONDS = 2.0

Seconds of signal a sweep window shows by default.

This is what sets the decimation ratio, and it matters far more than it looks. Without a time base, a frame’s samples are simply spread across the whole window, so a 30 kHz stream read at 30 Hz puts ~1000 samples into ~760 columns – barely any decimation, a window covering 33 ms, a plot that repaints entirely every frame, and tens of MB/s on the wire. Fixing the window in time makes a column a fixed number of samples, which is what makes both the picture and the bandwidth behave.